1. Field of the Invention
The present invention generally relates to reconditioning systems for removing oil from oily liquids and, more specifically, to reconditioning systems for removing tramp oil from coolants used in machining centers.
2. Description of Related Art
Machining centers or machine tools commonly have problems associated with tramp oil, such as mill oil, lubricant, or hydraulic fluid, collecting in coolant. The tramp oil reduces the cutting and cooling qualities of the coolant and is typically discarded after a limited number of hours. However, because the coolant is considered hazardous waste, it is very expensive to handle and discard.
One alternative is to remove the tramp oil from the coolant with an oil skimmer so that the life of the coolant can be extended. However, each of the four types of conventional oil skimmers (disk skimmers, belt skimmers, floating tube or mop-rope type skimmers, and weir skimmers) are inefficient in removing tramp oil from the coolant. The disk skimmers require a relatively calm surface and a constant liquid level. The belt skimmers are typically at least three feet tall and unacceptable for use with conventional machine tools. The floating tube type skimmers work well in large coolant systems, ponds, lakes, rivers or oceans, but there size prohibits use in conventional machine tools. Furthermore, the conventional floating tube skimmers remove far too much coolant along with the tramp oil. The weir skimmers remove as much coolant as tramp oil.
Additionally, the machine tools commonly have problems with bacteria and fungus growing in the coolant. The bacteria causes rancid odors and conditions that can cause operators to develop dermatitis. Typically additives are used to control the bacteria. Conventional additives such as biocides, however, can cause chemical and/or ph changes in the coolant which can degrade the performance of the coolant.
Accordingly, there is a need in the art for a coolant reconditioning system which efficiently removes tramp oil, reduces bacterial growth, causes no ph or chemical change in the coolant, is convenient to use with conventional machine tools, does not harm equipment, is portable, provides consistent coolant quality, and requires little or no consumables.